Notes on certain Blood- Inhahiting Protozoa. 237 



Mr W. S. Perrin has lately published (Archiv fur Protis- 

 tenkunde, Bd. vii. Heft 1, 1906) an account of a primitive 

 trypanosome, Trypanosoma balbianii, where he has described 

 a spiral band of chromatin which contains a thread-like 

 karyosome. The stage illustrated in Perrin's fig. 10 shows 

 a spiral of chromatin and a separate longitudinal thread, the 

 karyosome. In the ordinary condition of Trypanosoma 

 balbianii, the karyosome is not so clearly differentiated. The 

 stage shown in fig. 10 of Perrin's paper resembles the state 

 of affairs in the Trypanosoma brucei with the spiral and the 

 line, though in this last-named form there is, of course, the 

 well-developed blepharoplast, and usually the central somatic 

 nucleus. It is interesting to note that these forms replace 

 one of the hypothetical figures in the series of diagrams 

 which Perrin published in the above-mentioned paper to 

 illustrate the connection between Trypanosoma balbianii and 

 Trypanosoma noctuce. 



1 have no suggestion to offer as to how these forms 

 appeared in my material ; they were evidently absent from 

 the infections studied by Prowazek, as he makes no mention 

 of them, and they are far too striking to have escaped the 

 notice of this observer had they been present. Possibly 

 these specimens may be reversions to a more primitive 

 condition, due to the fact that the trypanosome has been 

 propagated by artificial transference from host to host for 

 a considerable time without passing any period in the 

 alimentary tract of Glossina, which is the natural method of 

 infection. The forms I have here described may perhaps be 

 a reversion to the one host type from which the ordinary 

 trypanosome developed. 



2. Trypanosoma pythonis, n.sp. 



This hsemosporidian is parasitic in the blood of an African 

 python from the Gambia. I have, through the courtesy of 

 Dr Logan Taylor, had the opportunity of looking through 

 some films made from the blood of an infected animal, and 

 I am indebted to him for the permission to publish the 

 results. 



The parasite in question is a fairly large organism, 



